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Condensed Suggestions 



STEEL WOHpl^S 




MILLER, METCALF & PARKIN. 

136 First Ave., Pittsburgh, Pa. 



NEW YORK -^^ CHICAC 

480 PEARL STREET. 64-66 S. CLINTON ST. 






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copyright 1888, by 
Miller, Metcalf & parkin, 



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CandensEd SuggBstinns . 

for StEEl WDTkEPS. 




riALcTCeil&Co.BustDji. 534 



Miller, Met calf & Parkin, 



O. SHEPARD * CO., PRINTERS, CHICAGO. 



Oh llHHEAiiiHG. 



OWING to the fact that the operations of roll- 
ing or hammering steel make it very hard, 
it is frequently necessary that the steel should be 
annealed before it can be conveniently cut into 
the required shapes for tools. 

Annealing or softening is accomplished by heat- 
ing steel to a red heat and then cooling it very 
slowly, to prevent it from getting hard again. 

The higher the degree of heat, the more will 
steel be softened, until the limit of softness is 
reached, when the steel is melted. 

It does not follow that the higher a piece of 
steel is heated the softer it will be when cooled, 
no matter how slowly it may be cooled; this is 
proved by the fact that an ingot is always harder 
than a rolled or hammered bar made from it. 

Therefore, there is nothing gained by heating 
a piece of steel hotter than a good, bright, cherry 
5 



CONDENSED SUGGESTIONS 



red; on the contrary, a higher heat has several 
disadvantages : First — If carried too far, it may 
leave the steel actually harder than a good red 
heat would leave it. Second — If a scale is raised 
on the steel, this scale will be harsh, granular 
oxide of iron, and will spoil the tools used to 
cut it. It often occurs that steel is scaled in this 
way, and then, because it does not cut well, it is 
customary to heat it again, and hotter still, to 
overcome the trouble, while the fact is, that the 
more this operation is repeated, the harder the 
steel will work, because of the hard scale and the 
harsh grain underneath. THIRD — A high scaling 
heat, continued for a Uttle time, changes the 
structure of the steel, destroys its crystalline prop- 
erty, makes it brittle, liable to crack in hardening 
and impossible to refine. 

Again, it is common practice to put steel into 
a hot furnace at the close of a day's work and 
leave it there all night. This method always gets 
the steel too hot, always raises a scale on it, 
and, worse than either, it leaves it soaking in the 
fire too long, and this is more injurious to steel 
than any other operation to which it can be 
subjected. 

6 



FOR STEEL WORKERS. 



A good illustration of the destruction of crys- 
talline structure by long continued heating may 
be had by operating on chilled cast iron. 

If a chill be heated red hot and removed from 
the fire as soon as it is hot, it will, when cold, 
retain its peculiar crystalline structure ; if now it 
be heated red hot, and left at a moderate red for 
several hours — in short, if it be treated as steel 
often is, and be left in a furnace over night, it 
will be found, when cold, to have a perfect amor- 
phous structure, every trace of chill crystals will 
be gone, and the whole piece be non-crystalline 
gray cast iron. If this is the effect upon coarse 
cast iron, what better is to be expected from fine 
cast steel ? 

A piece of fine tap steel, after having been in 
a furnace over night, will act as follows : 

It will be harsh in the lathe and spoil the cut- 
ting tools. 

When hardened it will almost certainly crack ; 
if it does not crack it will have been a remark- 
ably good steel to begin with. When the temper 
is drawn to the proper color and the tap is put 
into use, the teeth will either crumble off or crush 
down like so much lead. 



CONDENSED SUGGESTIONS 



Upon breaking the tap, the grain will be coarse 
and the steel brittle. 

To anneal any piece of steel, heat it red hot ; 
heat it uniformly and heat it through, taking care 
not to let the ends and corners get too hot. 

As soon as it is hot, take it out of the fire, the 
sooner the better, and cool it as slowly as possible. 
A good rule for heating is to heat it at so low a 
red that when the piece is cold it will still show 
the blue gloss of the oxide that was put there by 
the hammer or the rolls. 

Steel annealed in this way will cut very soft ; 
it will harden very hard, without cracking", and 
when tempered it will be very strong, nicely 
refined, and will hold a keen, strong edge. 



h^-^^^Q 



Oh Heating to pol^GE 



FULLY as much trouble and loss are caused 
by improper heating in the forge fire as in 
the tempering fire, although steel may be heated 
safely very hot for forging if it be done properly ; 
but any high degree of heat, no matter how uni- 
form it may be, is unsafe for hardeniiig. 

The trouble in the forge fire is usually uneven 
heat, and not too high heat. Suppose the piece 
to be forged has been put into a very hot fire, 
and forced as quickly as possible to a high yellow 
heat, so that it is almost up to the scintillating 
point. If this be done, in a few minutes the out- 
side will be quite soft and in nice condition for 
forging, while the middle parts will be not more 
than red hot. The highly heated soft outside will 
have very httle tenacity: that is to say, this part 
will be so far advanced toward fusion that the 
particles will shde easily over one another, while 
9 



CONDENSED SUGGESTIONS 



the less highly heated inside parts will be hard, 
possessed of high tenacity, and the particles will 
not slide so easily over each other. 

Now let the piece be placed under the hammer 
and forged, and the result will be as shown in 
figure I. 

The soft outside will yield so much more readily 
than the hard inside that the outer particles will 
be torn asunder, while the inside will remain 
sound, and the piece will be pHched out and 
branded "burned." 

Suppose the case to be reversed and the inside 
to be much hotter than the outside : that is, that 
the inside shall be in a state of semi-fusion, while 
the outside is hard and firm. 

Now let the piece be forged and we shall have 
the case as shown in figure 2. The outside will 
be all sound and the whole piece will appear per- 
fectly good until it is cropped, and then it is found 
to be hollow inside, and it is pitched out and 
branded " burst." 

In either case, if the piece had been heated soft 
all through, or if it had been only red hot all 
through, it would have forged perfectly sound and 
good. 



FOR STEEL WORKERS. y 



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,>^->-"^^ 



F.GURE 1. 



J 

Figure 2. 



CONDENSED SUGGESTIONS 



If it be asked, why then is there ever any neces- 
sity for smiths to use a low heat in forging, when a 
uniform high heat will do as well? We answer — 

In some cases a high heat is more desirable to 
save heavy labor, but in every case where a fine 
steel is to be used for cutting purposes, it must 
be borne in mind that very heavy forging refines 
the bars as they slowly cool, and if the smith heats 
such refined bars until they are soft, he raises the 
grain, makes them coarse, and he cannot get 
them fine again unless he has a very heavy 
steam hammer at command and knows how to 
use it well. 

In following the above hints there is a still 
greater danger to be avoided : that is incurred 
by letting the steel lie in the fire after it is prop- 
erly heated. When the steel is hot through it 
should be taken from the fire immediately and 
forged as quickly as possible. 

"Soaking" in the fire causes steel to become 
"dry" and brittle, and does it more injury than 
any bad practice known to the most experienced. 



Ok HeatiHg. 



OWING to varying instructions on a great 
many different labels, we find at times a 
good deal of misapprehension as to the best way 
to heat steel ; in some cases this causes too much 
work for the smith, and in other instances dis- 
asters follow the act of hardening. There are 
three distinct stages or times of heating : 

First, for forging. 

Second, for hardening. 

Third, for tempering. 

The first requisite for a good heat for forging is a 
clean fire and plenty of fuel, so that jets of hot air 
will not strike the corners of the piece; next, the 
fire should be regular, and give a good uniform 
heat to the whole part to be forged. It should be 
keen enough to heat the piece as rapidly as may 
be, and allow it to be thoroughly heated through, 
without being so fierce as to overheat the corners. 
13 



CONDENSED SUGGESTIONS 

X. 

Steel should not be left in the fire any longer 
than is necessary to heat it clear through, as 
"soaking" in fire is very injurious; and on the 
other hand it is necessary that it should be hot 
through to prevent surface cracks, which are caused 
by the reduced cohesion of the overheated parts, 
which overlie the colder centre of an irregularly 
heated piece. 

By observing these precautions a piece of steel 
may always be heated safely, up to even a bright 
yellow heat, when there is much forging to be done 
on it ; and at this heat it will weld well. 

The best and most economical of welding fluxes 
is clean, crude borax, which should be first thor- 
oughly melted and then ground to a fine powder. 
Borax prepared in this way will not froth on the 
steel, and one-half of the usual quantity will do the 
work as well as the whole quantity unmelted. 

After the steel is properly heated, it should be 
forged to shape as quickly as possible, and just as 
the red heat is leaving the parts intended for cut- 
ting edges, these parts should be refined by rapid 
light blows, continued until the red disappears. 

For the second stage of heating, for hardening, 
great care should be used ; first, to protect the 
14 



FOR STEEL WORKERS. 



cutting edges and working parts from heating 
more rapidly than the body of the piece; next, 
that the whole part to be hardened be heated 
uniformly through, without any part becoming 
visibly hotter than the other. A UNIFORM heat, 
as low as will give the required hardness, is the 
best for hardening. 

BEKR IN 7WVIND, 

that for every VARIATION OF HEAT, which is 
great enough to be seen, there will result a 
VARIATION IN GRAIN, which may be seen by 
breaking the piece; and for every such variation 
in temperature, there is a very good chance for a 
CRACK to be seen. Many a costly tool is ruined 
by inattention to this point. 

The effect of TOO HIGH HEAT is to OPEN THE 
(.RAIN ; to make the steel COARSE. 

The effect of an irregular heat is to cause 
IRREGULAR grain, irregular strains and CRACKS. 

As soon as the piece is properly heated for 
hardening, it should be promptly and thoroughly 
quenched in plenty of the cooling medium, water, 
brine, or oil, as the case may be. 

An abundance of the cooling bath, to do the 
15 



CONDENSED SUGGESTIONS 



work quickly and uniformly all over, is very 
necessary to good and safe work. 

To harden a large piece safely, a running stream 
should be used. 

Much uneven hardening is caused by the use 
of too small baths. 

For the third stage of heating, to temper, the 
first important requisite is again UNIFORMITY. 
The next is TIME. The more slowly a piece is 
brought down to its temper, the better and safer 
is the operation. 

When expensive tools, such as taps, rose cut- 
ters, etc., are to be made, it is a wise precaution, 
and one easily taken, to try small pieces of the 
steel at different temperatures, so as to find out 
how low a heat will give the necessary hardness. 
The lowest heat is the best for any steel, the 
test costs nothing, takes very little time, and very 
often saves considerable losses. 



Oh TElWPEt^. 



THE WORD temper, as used by the steel 
maker, indicates the amount of carbon in 
steel ; thus, steel of high temper, is steel contain- 
ing much carbon ; steel of low temper, is steel 
containing little carbon ; steel of medium temper, 
is steel containing carbon between these limits, 
etc., etc. Between Ihe highest and the lowest we 
have some twenty divisions, each representing a 
definite content of carbon. 

As the temper of steel can only be observed 
in the ingot, it is not necessary to the needs of 
the trade to attempt any description of the mode 
of observation, especially as this is purely a matter 
of education of the eye, only to be obtained by 
years of experience. 

Likewise, the quality of steel cannot be deter- 
mined from the appearance of the fracture of a bar 
17 



CONDENSED SUGGESTIONS 



as it comes from the hands of the manufacturer. 
This appearance is determined, in the main, by the 
heat at which the bar is finished, and therefore one 
end of a long bar (and especially of a hammered 
bar) may show a coarse, and the other end, a fine 
grain, where the whole bar will be well suited for 
the purpose intended. Two tools properly heated, 
forged and hardened (one from each end of such a 
bar) will, if broken, show fractures similar in color 
and grain. 

The act of tejnpering steel is the act of giving 
to a piece of steel, after it has been shaped, the 
hardness necessary for the work it has to do. 
This is done by first hardening the piece, generally 
a good deal harder than is necessary, and then 
toughening it by slow heating and gradual soft- 
ening until it is just right for work. 

A piece of steel properly tempered should always 
be finer in grain than the bar from which it is 
made. If it is necessary, in order to make the 
piece as hard as is required, to heat it so hot that 
after being hardened it will be as coarse, or coarser 
in grain than the bar, then the steel itself is of too 
low temper for the desired work. In a case of this 
kind, the steel maker should at once be notified 
i8 



FOR STEEL WORKERS. 



of the fact, and could immediately correct the 
trouble by furnishing higher steel. 

Sometimes an effort is made to harden fine steel 
without removing (by grinding or other method) 
the scale formed in rolling, hammering or anneal- 
ing. The result will generally be disappointing, 
as steel which would harden through such a 
coating would be of too high temper where the 
scale was removed. 

This surface scale is necessarily of irregular 
thickness and density, is oxide of iron — not steel 
— and therefore will not harden, and is to a 
certain extent a bad conductor of heat. It should 
therefore be removed in every case to insure the 
best results. 

If a great degree of hardness is not desired, as 
in the case of taps, and most tools of complicated 
form, and it is found that at a moderate heat the 
tools are too hard and are liable to crack, the 
smith should first use a lower heat in order to 
save the tools already made, and then notify the 
steel maker that his steel is too high, so as to 
prevent a recurrence of the trouble. In all cases 
where steel is used in large quantities for the same 
purpose, as in making of axes, springs, forks, etc., 
19 



CONDENSED SUGGESTIONS 



there is very little difficulty about temper, because, 
after one or two trials, the steel maker learns what 
his customer reqviires, and can always furnish it 
to him. 

In large, general works, however, such as a 
rolling mill and nail factory, or large machine 
works, or large raih'oad shops, both the maker 
and worker of the steel labor under great disad- 
vantages from want of a mutual understanding. 

The steel maker receives his order and fills the 
sizes, of tempers best adapted to general work, and 
the smith usually tries to harden all tools at about 
the same heat. The steel maker is right, because 
he is afraid to make the steel too high or too 
low for fear it will not suit, and so he gives an 
average adapted to the size of the bar. 

The smith is right, because he is generally the 
most hurried and crowded man about the estab- 
lishment. He must forge a tap for this man, a 
cold nail knife for that one, and a lathe cutter 
for another, and so on ; and each man is in a 
hurry. 

Under these circumstances he cannot be ex- 
pected to stop and test every piece of steel he 



FOR STEEL WORKERS. 



uses, and find out exactly at what heat it will 
liarden best and refine properly. 

He needs steel that will all harden properly at 
the same heat, and this he usually gets from the 
general practice among steel makers of making 
each bar of a certain temper, according to its size. 

But if it should happen that he were caught 
with only one bar of say inch and a quarter 
octagon, and three men should come in a hurry, 
one for a tap, another for a punch, and another 
for a chilled roll plug, he would find it very difii- 
cult to make one bar of steel answer for all of 
these purposes, even if it were of the very best 
quality. 

The chances are that he would make one good 
tool and two bad tools ; and when the steel maker 
came around to inquire, he would find one friend 
and two enemies, and the smith puzzled and in 
doubt. 

There is a perfectly easy and simple way to 
avoid all of this trouble ; and that is, to write 
after each size the purpose for which it is wanted, 
as for instance : Track tools, smith tools, lathe 
tools, taps, dies, cold nail knives, cold nail dies, 
hot nails, hot or cold punches, shear knives, etc.. 



CONDENSED SUGGESTIONS 

• • • • • X 

etc. This gives very little trouble in making the 
order, and it is the greatest relief to the steel 
maker. It is his delight to get hold of such an 
order, for he knows that when it is filled he will 
hardly ever hear a complaint. 

Every steel maker worthy of the name knows 
exactly what temper to provide for any tool, or if 
It is a new case, one or two trials are enough to 
inform him, and as he always should have twenty 
odd tempers on hand, it is just as easy — and far 
more satisfactory to both parties — to have it made 
right as to have it made wrong. 

For these reasons we urge all persons to specify 
the work the steel is to do, then the smith can 
harden all tools at about the same heat, and he 
will not be annoyed by complaints, or hints that 
he does not do his work well. 



pUHHflCES, 



WE present sketches of a cheap and handy- 
furnace for use in a blacksmith's shop, 
adapted especially for heating steel, and more 
particularly for heating steel for hardening. 

The furnace is so simple that the sketches need 
no explanation ; for binders, ten pieces of old rail 
about six feet long with one end set in the ground, 
and the tops tied by |-in. rods are all that is 
necessary, with a piece of iron about 3 x | in. 
running around near the top, and set in flush 
with the bricks. 

The distinctive features of this furnace are the 
fire bed and a good damper on the stack. In an 
experience of many years we have found nothing 
better than the Tupper grate bar with half-inch 
openings. These bars set in as shown make a 
level, permanent bed, and give an evenly distrib- 
uted supply of air to the fuel. In such a furnace 
as this, one set of bars will last for years and 
remain level. 




B 
END VIEW 

'29 6 3 . I 2 3 f SB 

»al l- w l I- I ' J 1 1 

Scale :,! = I foot. 



Sidick I5'to20'hi^h. 



SECT10N:A.B. 

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CONDENSED SUGGESTIONS 



While on the subject of grate bars we may as 
well say that the satisfactory and safe working of 
this furnace would be entirely defeated by any 
attempt to use either square wrought iron bars 
or ordinary straight cast iron bars. Such bars 
always warp, get pushed out of place, and allow 
a rush of air through at one place, and no air 
at another. This causes hot and cold places in 
the furnace and produces uneven heating, which 
is the chief source of cracking in hardening; more- 
over, the air rushing through the large holes will 
burn the steel. A bar must be used which will 
remain level and in its place, and the smaller 
and more numerous the openings are, the better 
will be the result. 

Clean, hard coke is the only proper fuel for such 
a furnace and for such work. The furnace should 
be filled full up to the fore plate ; or better, a httle 
higher — with coke in pieces no larger than an 
ordinary man's fist — but the smaller the better. 

When it is used for heating for forging purposes, 
the damper may be left high enough to run the 
furnace as hot as may be required — if necessary, 
a welding heat can be obtained. 



FOR STEEL WORKERS. 



When used for hardening, the furnace should 
be got as hot as is needed before the steel is put 
into it; then when tlie steel is put in, the damper 
should be dropped down tight. 

The door, which is 12 in. high and 24 in, wide, 
should be nicely balanced by a lever and weight, 
with a rod in a handy place so that the operator 
can pull it up easily and turn over his pieces from 
time to time, so as to get his heat perfectly uniform. 

In the clear gas of a coke fire, the whole interior 
of a furnace can be seen easily, and every piece 
can be watched as it ought to be. Time, care, 
watchfulness, and absolute uniformity of heat, are 
the essentials necessary for success in hardening 
steel. 

Every large shop should have such a furnace, 
and should have one man trained to its use, to do 
the hardening and tempering for the whole shopf. 
Such a furnace in the hands of a careful man in 
any railroad shop in the country would pay for 
itself every year and save the man's wages besides. 

The furnace will consume very little coke at any 
time, and when not in use, with the damper down, 
it will stay hot a long time and waste the coke but 
a trifle. 



CONDENSED SUGGESTIONS 



There is no more absurd nor wasteful system 
than that of reqviiring a smith at his anvil to harden 
and temper his work. His fire is not fit to heat in, 
to begin with, and he never has time to do his work 
properly if it were. 

From such a furnace as is here described, we 
harden all sorts of tools : taps, small dies, large 
rolls, rotary shear knives, and shear knives as large 
as five feet long, which is the whole length of the 
furnace. 

The tempered steel which is best is that which 
is the finest in the grain and the strongest. The 
best way to test both grain and strength is to ham- 
mer out a piece to about i^ x i in., a foot or so in 
length, and temper to a high blue or pigeon wing, 
and when cold to break it off in little piecees with a 
hand hammer. 

A little practice will soon enable a man to deter- 
mine, first, whether he heated his piece to just the 
right point. The file and the appearance of the 
grain will determine this point. Next, when a little 
experience as to heat has been gained, he will 
know by the strength and grain whether his steel is 
really good, or whether it is " dry" and poor. 



FOR STEEL WORKERS. 



F= I N 7X I- L-V. 

The art of working steel can be acquired only by 
intelligent application. 

Some will never learn, and others seem to be 
imbued with the idea that twenty or thirty years' 
practice must necessarily qualify them as experts. 
In point of fact something new can be learned 
every day, and he is wise who will lay aside 
prejudice and change his mind whenever occasion 
requires it. 

We, as manufacturers, are always pleased to 
have Steel Workers visit us, and see for them- 
selves the care and attention which are given to 
the working of steel in every department, and 
we think they cannot fail to carry away some 
information which will be advantageous. 

Miller, Mktcalf & Parkin. 



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